Based on the long running Sunday Times column and the book of the same name - The Plot 34 Blog is Mark Keenan's take on the ups and downs of growing food at his Dublin allotment, in his garden, his greenhouse and on his indoor window sills. For aspiring urban farmers who appreciate the lighter aspects of the plot.

Thursday, June 2, 2011

Rooting Out the Ginger Ant

While most home grown foods generally taste better than shop bought, carrots - along with tomatoes and peas - are three crops that taste so outstandingly different, that a single serving will instantly break the resolve of even the most hardened of non believers.The taste of a home grown carrot is such a revealation that it should have any organic food cynic seeing through the dark. Homegrown carrots are just so many more times... carrotier.

The trouble is that carrots also happen to be many times more fussier into the bargain. Consider too that the carrot root fly - one of the most dogged and destructive pests known to allotment mankind - will always have the carrot grower's efforts firmly in its sights.

Lovely nubile juvenile carrots - the dream we strive for

For my first five years with my allotment, fellow growers marvelled at my bumper carrot crops. Initially, as a newbie to the food growing game, I didn’t understand what all the fuss was about. I sowed, I weeded and I harvested and that’s pretty much was all there was to it. Most years I’d take two sacks of near-perfect Nantes variety in September or October, bring them home, process them, freeze them and our family would enjoy them for most of the next twelve months. My fellow fly stricken growers continued to scratch their heads and attempted in vain to figure out by deduction how I managed to avoid the plague which, once it gets in on some allotment complexes, puts people off growing carrots completely.

Smug - how I felt after three years of perfect carrots. He told us the Whitehouse veg garden has great carrots - for now..

Personally I thought my past successes were down to complementary planting - sowing lines of onions between the carrots. The onion smell is thought to confuse the carrot fly. But last year, for the first time, both my sowings of carrots were wiped out by the pesky varmint despite the usual flanks of onions. The first signs are the stunted foliage which takes on a reddish tinge.I have no idea what changed - but if I’m going to have another go this year, I’ll have to think through a strategy of sorts. Our carrots were really missed last year but on the other hand I don’t fancy all the effort that goes into them without some guarantee of results.

I refuse to show a proper wiggling carrot fly maggot..

Here’s the fussy carrot bit: The soil has to be dug deep - at least two feet because the main tap root we eat does not account for the satelite “hair” roots which delve at least as deep again and then spread out in all directions. It can’t be too waterlogged or too dry. It needs to be dug extra fine - too many stones and you end up with many fingered and split carrots.

Right from germination they’re succeptible to being smothered by weeds, which also tend to spring up faster than usual in extra refined soil. That’s why I've learned to prepare my carrot bed and then leave it sit for two weeks to allow whatever weed seeds are still in the ground to sprout and identify themselves before removing them.

Unlike many other crops, carrots can’t be started in a tray on a windowsill or in a greenhouse where you can keep and eye on them and keep them safe. The seeds need to be sown in situ.

They’re also fussy about germinating conditions and generally won’t sprout unless there’s a few consecutive days of ten degrees plus temperatures. They don’t like too much nitrogen in the soil - that might be caused by too much fertiliser or manure (they go hairy as a result) but they do need a mineral rich or they stay small and the roots don’t swell up. When the seeds do sprout they’re also prone to drought.

Changed me mind...lots of them at once

Meantime the carrot fly - which looks like a shiny black flying ant with a reddish head is out. It's said to have the ability to smelling carrot foliage from as much as ten miles away. Thinning the carrots as they grow to allow them enough space is a process that sends up scent and brings them from all over.

Because I suffered last year, it is a certainty that there are carrot fly larvae in the ground at Plot 34, ready to hatch out this month - the first phase of a two part cycle. The flies travel between a hundred and four hundred metres to find their target crop. There is no chemical available to treat them and government advice is to grow the following year’s carrots 2km away. Very practical Mr Government. Thanks.

Mr Government...tight trousers are back in and so are lamb chops

At allotment complexes in particular, once established, the fly is incredibly difficult to shake off. The hatching flies move straight to the carrot foliage and lay their eggs in cracks in the soil at the base of the plants. It takes two more months for these eggs to hatch into flies and lay more eggs. We live in hope however that the dreadful temperatures of the immediate past winter killed off the unwelome sleepers.

So I’m looking into the cost of buying a substance called enviromesh, a type of net curtain material with which I’m planning to cover the carrots. The idea here is to build a frame around them to the height I’d expect the foliage to grow - perhaps a foot and a half and then cover it with the mesh. The local DIY barn says they’re out of it at the moment (and they’re usually are out of whatever’s in season) but they say it normally costs twenty euro for a ten metre by a half metre roll of the stuff. That’s expensive for a carrot crop - but apparently it can be resused again and again.

The sort of grief you have to go through to make sure the carrot fly doesn't get through

Some growers simply create a two foot high barrier around the crop on the grounds that carrot fly don’t fly higher than that. My own view is that the wind could easily carry them up and drop them in. Or if they’re as determined as most people say, what’s to stop them simply shinning the boundary fence.

Another tip for avoiding the grub is to grow your carrots in the most exposed and windiest patch you have (he isn’t a strong flier and can’t cope with winds apparently). Keep nettles down as the fly uses them as a resting and vantage point.

Alternatively ditch the defences and grow one of the new resistant strains of carrot. Flyaway is an F1 hybrid carrot cloned to be flyproof and Resistafly is another. Much as I hate to sow hybrids, the clones of the grow your own world, I've sown Resistafly this year with its daft name and lack of pedigree, because I do love the taste of a home grown carrot.

Carrot Fly - right to reply: "Bzzzzzzzt bzzzzz bzzzzz zzzt!"

Finally you could bring in your own crack squad of heebie jeebies to go on the attack - in the last few years nematodes have been developed to find the bug in the soil and kill it. The problem is that this is an even more expensive solution than the enviromesh with most nematode doses costing over twenty quid anyways. Or you could do what many gardeners do and just give up.

But to Plot 34 the ginger ant is simply raising my hackles and throwing down a challenge. On guard ye little get....

(UPDATE FROM TWO MONTHS LATER IN JULY - I didn't bother with the environmesh in the end. A nearby allotment holder did, with mixed results. He can't get in to take out the weeds which have smothered his crop here and there - but 60% of his plants should make it.

Instead I sowed two types of carrots, a yellow heritage variety which simply didn't sprout at all and Resistafly of which about 65% has sprouted. These have remained amazingly intact with no pest attacks at all. However as my friend with the enviromesh noted, they look a bit too good to be true. A bit too "plastic" or something. So I suspect they'll taste different in some way. Watch this spot for further carrot updates.

About Me

My name is Mark Keenan. For the past six years I've been writing a column in the Irish edition of the Sunday Times newspaper called Plot 34. This relates to the running my allotment, the food I grow there and in my small suburban back garden, on my kitchen window sills and anywhere else I can fit it.
I am helped in this mission by my family - "Her Outdoors" is my patient better half. There's Plot 34's Self Appointed Head of Secret Tunnels - my intrepid assistant and eight year old son and our Waterer of Everything - our ebullient three year old daughter who loves to water everything, including her dad's shoes and socks. Recently we had a new arrival, our baby son Sean.
On occasion I'm offered unsolicited advice by my dad - who knows everything about everything. He's Plot 34's Expert on Everything (EOE).
I'm based in Dublin, Ireland and my 120 square metre allotment is located in the foot of the Dublin mountains at Bohernabreena.
I'm no expert in food growing but over four years I have learned the difference between a carrot fly and a vine weevil, a turnip and a swede, a dock and a hard place.
Be sure to check the archive above for more posts